NEW YORK, NY – DECEMBER 21: Rev. Al Sharpton (L), and Gwen Carr (R), Eric Garner’s mother, during a press conference denouncing the shooting deaths of two New York Police Department (NYPD) officers at the National Action Network on December 21, 2014 in the Harlem neighborhood of New York City. The press conference follows the execution style shooting of officers, Wenjian Liu and Rafael Ramos in Brooklyn on December 20, 2014 where the suspect was apparently motivated by the deaths of Eric Garner and Michael Brown.

NEW YORK — Civil rights leaders on Sunday condemned the ambush killings of two New York police officers and expressed fear that the backlash over the bloodshed could derail the protest movement that has grown out of the deaths of Michael Brown and Eric Garner.

In the hours after the killing of the officers, police union officials and politicians accused those who have protested the deaths of Garner and Brown of fanning anti-police fervor. The Garner and Brown families issued statements repudiating the officers’ killings, while civil rights leaders took to the airwaves to try to put some distance between the movement and the crime.

“To link the criminal insanity of a lone gunman to the peaceful protests and aspirations of many people across the country, including the attorney general, the mayor and even the president, is simply not fair,” said NAACP President Cornell William Brooks on CBS’s “Face the Nation.”

Brooks said the shootings were “certainly not a step forward” for the movement.

Officers Rafael Ramos and Wenjian Liu were gunned down at close range in their patrol car in Brooklyn on Saturday by Ismaaiyl Brinsley, who then committed suicide. Before the attack, Brinsley, 28, used the hashtags Shootthepolice, RIPErivGardner (sic) and RIPMikeBrown — references to two blacks who died at the hands of police.

In the wake of the ambush, former New York Mayor Rudy Giuliani lashed out at New York Mayor Bill de Blasio, President Barack Obama and Attorney General Eric Holder. Speaking on Fox News, Giuliani said: “We’ve had four months of propaganda starting with the president that everybody should hate the police.”

In a tweet, former New York Gov. George Pataki called the killings the “predictable outcome of divisive, anti-cop rhetoric of Attorney General Eric Holder and Bill de Blasio.”

The accusations stoked fears that gains made in the protest movement would be lost.

“We’ve been denouncing violence in our community,” no matter who the target is, said New York community activist Tony Herbert. He said he worries that the shooting will be used to discredit the larger cause:

“It sullies the opportunity for us to make inroads to build the relationships we need to build to get the trust back. This hurts.”

As thousands gathered in Denver’s City Park on Monday to celebrate the life and legacy of Martin Luther King Jr., speakers didn’t mince words: King’s message was not only about love and unity, they said, but it was about fighting for freedom and equality for everyone.